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Can a 747 airfoil be scaled down for smaller jet planes?
At the loss of its acrobatic ability, could an airfoil similar to the 747 be downsized to allow a small jet to climb higher and extend its range?
This plane with its wing profile is highly acrobatic, but has a range of only 400 statute miles compared to the 900+ miles that its propeller counterparts gets. I believe it has much to do with the type of airfoil. Jim Bede, the designer of the plane, originally used a propeller version meant for travel, not acrobatics. As time progressed the profile of the wing evolved for more stability and acrobatic performance instead of stability and range.
Here I have a BD-5J Micro Jet with a wing span of 13.5 ft.

and another version I call the BD-5HC High Cruise where I pasted on some 747 wings. Is it plausible to fly it in the same method as a 747 using lower altitude speed limits and increasing speed in higher altitudes?

I have another question related but with forward swept wings here, Are Foward Swept Wings for a Rear Propeller Airplane Feasible?

I’m not an authority on aerofoils but  a reliable way to increase the efficiency and therefore the range would be to use a larger aspect ratio wing.  The aerofoil will typically be chosen to be optimal for the altitude, loading, speed etc rather than the other way round.  As far as scaling goes, yes this does work reasonably well of the scaling factor isn’t too big; even model aircraft can use sections that are similar to big jets.

Jetliner's airfoils are optimised to travel at some 900 kmh at 10'000 m altitude, I don't think that that airplane can reach such speeds and altitudes. Sweeping the wing back alters CG and aerodynamic center position i.e. longitudinal stability; plus wing becomes structurally heavier and more difficult to build; plus it brings some positive effect only at high subsonic speed. To get a better answer it should be made clearer the mission of the airplane: flying fast, far, agile, high, ... ?

Re "As time progressed the profile of the wing evolved for more stability and acrobatic performance instead of stability and range." -- this is confusing.  Maybe delete one of the "stability"s?

My thought is that in engineering, things are intertwined in a way that leads us to oversimplify cause and effect.  Does the 747 perform the way it does because of the wing?  Or was that wing design required by the performance characteristics of the plane?  Advances in power plants tends to be the driving/limiting factor in airliner design, which in turn enables flight regimes that require a rethinking about wings.  The question is “can I make a BD5 perform in a way that will benefit from that wing?” and not “will that wing improve the performance of the BD5”.

There is a general, and fundamental reason why this won't work as you expect. You can scale the aerofoil, but you can't scale the air. (At this point I recall that all the aerodynamics I learnt was 40+ years ago). To get similar behaviour at different scales you need to fiddle with the Reynolds number. This is why wind tunnel testing is sometimes done at low (perhaps cryogenic) temperatures, amongst other things.

The propeller version BD5 flys up to 230 mph and the jet version up to 320 mph, cruising at 270 mph.  The wing for the the jet version is said to be "between the A and B versions" of the propeller craft.
First, the wing shape is more like a P51 Mustang for good reason.  Those planes had to be built strong for military duty and also had to be low in drag to fly a long way.  These so called "laminar wings" had nasty stall characteristics reminiscent of the shorter BD5 A wing. The 21 foot B wing was brought into the design after some crashes.  Interestingly, a sailplane version was also planned.

cruising and top speeds for propeller and jet versions are too low to benefit from a high subsonic swept wing design$^1$.

The main reason for loss of cruising range when converting to the jet is that the tiny turbine engine simply did not have the fuel efficiency of the propeller engine it replaced, especially at the higher cruising speeds.
Adding a larger wing only helps up to the point where the added weight is compensated by less drag at the design cruise speed from a lower AoA.
Going higher could be done with a straight wing provided thrust was available at those altitudes and sufficient oxygen was carried for the pilot.  The design should look more like a B-29 than a 747, or, perhaps more like this one, or, maybe this one.
The company that designed and produced the BD5 aircraft went bankrupt.  Buyer beware.
$^1$ the jet version, at 30000 feet, would exceed 500 mph TAS if thrust was sufficient

And quite importantly, that 747 is landing at about 150 kts.  That P-51 wing isn’t just strong, it also reduces landing/takeoff speeds which opens up considerable flexibility in where I can deploy ground-based interceptors in a dynamic war front.  And smaller brakes, smaller lift-spoiling requirements, non-reverser engines, all mean more fuel for range, more ammo.  Swept wings change where planes can land, which militarily is then tied into strategic decisions about aircraft carriers and aerial refueling capability.  Military deployment capability is itself a huge engineering variable.

Nice answer. Today, small jet engines have came a long ways in efficiency. Yes, an Oxygen supply maybe needed. Just like their is a perfect wing length for efficiency, I imagine their is an optimal jet engine size.


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What would be the general steps for making a flight in a biplane?
I'm a writer, the story I'm writing is set in 1942. It's an alternate history of sorts, so there's no pesky WW2 to worry about, but technology has developed in roughly the same way. As part of an action sequence, my character, Scarlet, is going to steal a biplane to escape pursuit. She has a pilot's license and knows how to fly, but until this point, she hasn't needed to actually show her stuff.
What I do need to know, in layman's terms, are the general procedures of how the flight would go, any preparation that might be needed, and approximate speeds.

The time (1942) is right for biplanes, but flying a plane, biplane or not, is not as easy as driving a car. Scarlet may have a license and know 'how to fly', but flying away in an unfamiliar plane (and not crashing) is something only highly experienced pilots, with thousands of hours in different planes, may be able to do.

@xxavier: Oh, come on! This might be true for complex aircraft, but given the time it is highly likely that Scarlet was trained on a very similar aircraft. No flaps, just basic instrumentation and a fixed prop. It can't get much easier than that, but it will exclude her from flying IFR.

You won't be able hand-waive away the rate of technological advancement without WWII. Make sure that you come up with a good reason for having such advanced machinery.

I think open collaboration between Russian, German, and American scientists would have had the same effect on technology as ww2 without all the bloodshed.

There were plenty of biplanes, as well as more advanced aircraft, before WWII, and biplanes continued in use during the war. The war did raise incentives for some technological development, but biased heavily toward military applications. I don't see any glaring technological anachronism in this question.

First follow @Jim's advice for getting the plane set up and the engine running.
A biplane is most likely a taildragger, which means that it has two main wheels and a third all the way in the back. This will give the plane a nose-high ground attitude, and taxiing to the runway will involve Scarlet to wiggle the plane left and right because the forward fuselage is obstructing her forward vision. This is not made easier by the fact that tandem two-place biplanes, the most common type, are flown from the back seat in order to get the center of gravity right.
Next, she should wait until engine temperature is high enough to run the engine at full load. I would expect that in a pursuit she skips that step but will worry that oil temperature has not reached the required temperature. The next step would be the magneto check which she will also skip.
In the takeoff run she will first orient the aircraft into the wind and then gently apply throttle so the aircraft doesn't end up in a headstand (meaning the propeller pulls the nose into the ground without the wheels moving). This also requires her to pull the stick all the way aft so the empennage (horizontal tail) keeps the tail low. A headstand is shown in the second picture of the second linked answer (this one).
Airfields back then were mostly round grassy patches, so the take-off direction could be freely selected in order to take off directly into the wind. However, you might want to add some suspense when Scarlet finds her biplane at the wrong end of the field and has no time to taxi across it, but takes off with a tailwind. This will make the takeoff run longer and the climb after takeoff more shallow, so she might just barely escape collision with an obstacle there.
When the aircraft picks up speed she should reduce back pressure on the stick and move the stick to a roughly central position in order to reduce downforce on the tail so the tail can lift off the ground. Bonus points for mentioning the gyroscopic effect from the propeller as the aircraft lifts its tail which requires the brief application of rudder to keep the nose pointed into the desired direction.
Liftoff is rather unspectacular and happens when the aircraft is fast enough. However, if elevator trim is set the wrong way, the aircraft will stay on the ground for too long (too much nose-down trim) or lift off too early at a too slow speed (too much nose-up trim). Trim means that either a spring in the elevator linkage or a small auxiliary flap is set such that it pulls the elevator to a certain deflection angle. This is helpful for adjusting control forces according to the desired flight speed and center of gravity location, but if it is set the wrong way on takeoff, Scarlet might be surprised by unusual stick forces.
While the takeoff is flown at full rich mixture, once in the air Scarlet should adjust the fuel to air mixture in the engine according to flight height. You might want to add a dramatic moment where the engine runs rough or even stutters due to too lean mixture.
After that, the escape should be easy.

@dalearn: Yes, agreed. I added a link.

You never cease to impress @PeterKämpf. Mastery not only in explaining engineering, but now also in prose!

"After that, the escape should be easy." True, although she might eventually prefer to land the plane herself.

Simplified, for a fiction book in my best attempt.
Step one you'll need to identify a biplane that had electric start, unless someone's available to prop the plane...though the character could do this on their own.
Has fuel, no water in fuel,
Wheels chocked,
Brakes set,
Master switch on,
Both mags on,
Start engine(ignition switch or prop start),
Pull wheel chocks(this would be prior to starting engine if electric start),
Climb in(this would be prior to starting engine if electric start),
Run up and adjust mixture,
Check controls for free movement,
Check control surface deflection,
Idle engine once at operating temp,
Release brakes,
Stick back for ground maneuvers in a taildragger unless it's windy,
Point towards open Tarmac and go full throttle, assuming radio calls and finding the actual runway aren't necessary in such a daring escape
Happy writing

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What is this plastic device inside the plane window?

I saw this on a recent domestic flight. It was glued on all the windows of the plane, behind the first layer of plastic. What is it and its purpose?

What flight number? Do you happen to know the model of the plane?

@vasin1987 it either has a winglet (which narrows it down by... not a lot) or was flying in close formation with another plane. ;)

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Do aircraft automatically send a message to the ground if there is a catastrophic failure?
For example, if there is a engine failure, it will be displayed on EICAS as a CAS message. As per my knowledge, the pilot will initiate the contact with any ground station nearby for guidance to land safely. Iis there any equipment in the aircraft to send the distress automatically when there is any major failure?

The only system that notifies anyone on the ground is the ACARS that the other answers mentioned. There are all kinds of notifications to the pilots, and usually guidance to help them resolve it. Look up EICAS. There's not a notification to ATC or dispatchers, only maintenance. If the pilots can't resolve the problem they will ask for whatever assistance they need.
In a complex aircraft there are lots of false alarms, sensor failures, momentary problems, etc. that the pilots are able to work out without a problem. It wouldn't be helpful to notify people on the ground for all these. They can rarely do much to help anyway. If the pilots need to divert or declare emergency then they will alert etc.
Sometimes they will confer with their dispatcher or maintenance personnel about what they need to do. The ACARS messages can probably help with this. They can discuss with dispatchers if they need to go to a specific terminal where there are personnel that can fix a specific problem and the dispatcher helps them determine if they have fuel to make it there.
The pilot is the one that's makes the decisions, so there's really no advantage to sending a distress signal to the ground since all they could really do is to contact the pilots.

Most commercial aircraft have a system called ACARS that can be used to transmit flight information and messages between the ground and the aircraft. In many cases, the ACARS is configured to transmit flight data automatically (engine performance, airspeed, altitude, etc) that would include error messages/warnings from the various systems onboard.

Thanks @Geoff. what i understand is  ACARS will  help in maintenance and like you mentioned its used to transmit flight information and messages. Is there any thing that informs any near by ATC or ground station, that can contact the crew of aircraft and help them when a catastrophic failure in any of the system occurs.

The ACARS transmissions usually go to an airline's dispatch center or other ground crew, but not really to ATC. ATC does however have radar capabilities that could give them clues the something is wrong, for example drastic changes in speed, altitude, etc. Beyond that, it's really pilots to communicate emergencies either via radio or squawk code (7500 = hijacking, 7600 = tech/radio failure, 7700 = mayday)

There is nothing formally standardized as far as I know however newer Rolls Royce jet engines (and presumably those from other major manufacturers) do have a continuous inflight data link that reports engine data in real time to their reporting centers. You can read up on it here as well as this discussion with lots more info.

Aerospace Operations Centres are able to track the health of thousands
  of engines operating worldwide by using onboard sensors and live
  satellite feeds. Rolls-Royce are world leaders at equipment health
  management (EHM)

The centers are potentially able to detect certain emergencies remotely based on the parameters reported.

Since you note the pilot making contact presumably with the radio: Pilots can report an emergency without the use of a radio by Squawking 7700 on the transponder as well.

Note though, that those messages not distress signals. They are for maintenance purposes, so they'll go to someone at the airline's maint. dept., not really to anyone who is equipped to help the crew with an emergency.

@TomMcW so you are saying there is no equipment to identify the failure in the aircraft and help the flight crew as soon as the failure of any system occur unless the pilot asks for it?

@sambasiva I went ahead and added an answer

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Why does flying not have any age restrictions like driving does?
I read an autobiography about Vicki Van Meter, who, with her instructor, flew across the United States at age 11 in 1993. Why could someone of that age not drive with the instructor?
Does it have to do with a different set of principles that flying has as opposed to driving?

There's a lot more drivers than pilots. If you let one 11 years old drive in the streets soon where you got thousands more and it will create a huge  safety problem. And maybe more important, to become a pilot you do need a lot more commitment than to learn how to drive

Vicky was not Pilot in Command.

@PaulOgilvie - she still wouldn't have been allowed behind the wheel of a dual-control car driving on public roads in most jurisdictions, even though the situation is exactly the same, with the instructor being in control of the vehicle.

@CrossRoads Please don't post answers as comments.

2D space is much more crammed with moving objects and obstacles than 3D space.

@Jules Are you sure of that? Is there a law prohibiting a non-licensed driver manipulating the controls? e.g. a passenger shifting or holding the steering wheel

@SteveKuo - It depends on your jurisdiction, obviously, and in many it may not be clear.  In mine, for instance, the Road Traffic Act 1988 Section 87 says "It is an offence for a person to drive on a road a motor vehicle [...without...] a licence authorising him to drive a motor vehicle" (and similarly allowing a person to so do is also an offence in the same section).  As you cannot acquire such a licence legally until you're 17,  then "driving" on a road is not legally possible. ...

... and because "driving" is interpreted broadly to include anything that involves control of a vehicle, it looks like it would apply in the case you describe.

Short answer: the US government agreed with you 3 years after her record flight.
In the FAA reauthorization act of 1996, the following clause was added to 49 U.S. Code § 44724 - Manipulation of flight controls:

(a)Prohibition.—No pilot in command of an aircraft may allow an individual who does not hold—
(1) a valid private pilots certificate issued by the Administrator of the Federal Aviation Administration under part 61 of title 14, Code of Federal Regulations; and
  (2) the appropriate medical certificate issued by the Administrator under part 67 of such title,
  to manipulate the controls of an aircraft if the pilot knows or should have known that the individual is attempting to set a record or engage in an aeronautical competition or aeronautical feat, as defined by the Administrator.

Per 14 CFR 91 (can't find the exact text right now, but I know this is true from my flight training), you cannot obtain a student pilot's license until age 14 (so, no soloing until then, let alone a long-distance trip) and a private pilot's license until age 16 (for gliders).  You can't get a private pilot's license for your typical single engine aircraft until age 18.  A sport pilot's license is possible by age 17, but is limited on the aircraft you can fly (that said, a coast-to-coast trip has been flown in a Piper J-3 Cub, which fits under the sport pilot license) and conditions you can fly in.
Hence, it would not presently be legal to do what Vicki did in 1993.  According to a NY Times article covering another young pilot, Jessica Dubroff (aged 7 at the time of her fatally unsuccessful attempt at a coast-to-coast flight):

Jessica was breaking no aviation rules when she flew.  The plane had dual sets of controls, meaning that the flight instructor was legally considered in charge and had the ability to take control instantly, though the plans called for Mr. Reid to take over only in an emergency.  But within hours of the crash, Federal authorities announced that they would re-examine existing regulations on underage pilots.

This would have preceded the addition to the USC quoted above.

Wasn't the FAA regulation change in response to someone crashing while trying to set a "youngest person" record?

@jamesqf: Yes. https://en.wikipedia.org/wiki/Jessica_Dubroff

Found an NY Times article that covers it too, and added to the answer -- thanks all! http://www.nytimes.com/1996/04/12/us/girl-7-seeking-us-flight-record-dies-in-crash.html

Strictly speaking by the wording given, it wouldn't be illegal for an 11 year old to fly as long as they're not attempting to set a record or engaging in a competition unless "aeronautical feat" has been defined so broadly as to encompass flying a plane at all.

Agreed.  I know of many private pilots who'll give temporary control of the aircraft to an unlicensed friend (while flying) under safe conditions, just so that they can "feel" like they are flying (usually means straight and level flight).  The only CFRs I've found to say you can't do that apply to civil operations (14 CFR 121), air carriers (14 CFR 125), and flight with seating for 20+ pax/or an aircraft with payload capacity >6,000 lbf (14 CFR 135).

Is there an upper age limit? Does a license expire upon reaching an old age?

That is an absurdly narrow regulation.  And doesn't actually answer the question, as it is still possible for somebody to repeat the feat in the question, as long as they are not attempting to break a record while doing so.

@Cloud -- A guy in my glider club was 86 when we received his private pilot's license.  He kept exercising his private pilot's license (legally) until he died (in his bed) in his 90s.  Granted, the club put certain restrictions on him, but they weren't from the FAA.
@ Jules -- Insofar as I read the OP's question, they ask about age limits in flying (on the young end) and the why, not necessarily whether or not someone could perform the feat in question.  Can you show me what you're seeing?

@Cloud You need to pass a medical examination every few years to hold a pilots license, so age starts to have an effect (if you've had three heart attacks and a TIA, probably no more flying), but as long as someone is healthy there's no fixed upper limit.

It depends on the aircraft type as well.  Gliders only require self-certification for medical wellness.

@Cloud: Depends on the type of operation; a U.S. ATP/CP isn't valid for piloting commercial flights past age 60.

@Vikki It was changed to 65 in 2007 for ATP. That only applies to Part 121 (scheduled air carriers, i.e. airlines,) though, as I recall. I don't think there's a limit for commercial, as long as you can keep passing a Class 2 medical.

@reirab -- the air service provider at my airport just took advantage of that.  They are providing services as an air charter service under Part 135, and they do not have an age limit (providing you can keep passing the required medical).

I can't give an authoritative answer because I doubt one exists, but one huge difference between cars and planes is that all aircraft used for primary instruction can be flown from either seat. Both legally, and physically.
It's almost always entirely possible for a pilot to conduct an entire flight by themselves from the second seat, save perhaps some small logistical issues with the location of a switch or two.
To that end, it's not possible to fly in the front seat of a trainer without being at the controls. Therefore any passenger, in either seat, is sat in a position of being able to take control of the aircraft.
In addition to that, while aircraft are often designed with one primary seat in mind (normally the left hand seat), there are rarely any legal restrictions that say a training aircraft can't be commanded from the right.
This differs hugely from a car which, firstly, is designed specifically to be driven from one side or another. An instructor in the passenger seat may have a SUBSET of controls, but sometimes not and therefore can't fully control the vehicle from that seat.

What about cars that do have full-dual controls?

@Vikki Do those even exist? Simultaneous control inputs from two different people in a car sounds extremely dangerous. A fraction of a second of unexpected control inputs and you're run over by a truck or you've driven into a tree or concrete barrier at highway speeds. Airplanes tend to be much more forgiving than cars about fraction-of-a-second control inputs, except maybe when landing (and, I'd argue, probably even still then.) Airplanes react much more slowly to control inputs than cars do.

@reirab: If you're instructing someone who's still learning how to drive, the more control you can take when necessary, the better.

@Vikki Not sure that I'd agree. Example: a deer jumps out in front of you. One of you instinctively tries to dodge hard left. The other instinctively tries to dodge hard right. Either would have worked, but instead you've run straight into the deer. Also, for city driving, replace 'deer' with 'person' and the results are the same. There's no time for coordination between drivers in split-second reactions like that. When flying, there's usually a lot more time and things tend not to jump out right in front of you (except for birds, at least, and there's isn't much you can do about that.)

Also how would the mechanically even be possible? The controls in a car are basically a mechanical drive shaft

Driving requires a much faster reaction time.  Look at how the consensus process works inside a cockpit under healthy CRM.  Just having a brief "My airplane" / "Your airplane" is far too slow for typical driving events.
Even if we set aside those formalities and simply have the Co-driver "leap in when needed", events don't unfold that way.  Actually what happens is the Co-driver sees the emerging problem (truck pulling into their path) and the first thing she does is presume the Driver is going to handle it correctly. If the Co-driver leaps in too soon, 99% of the time she ends up needlessly wrestling the driver for control.  So the co-driver intervenes quite late, only when it's clear the Driver isn't doing the job. At this point, usually, your goose is cooked.
A classic example of this was the first fatal crash of someone letting the computer drive: the co-driver was attentive and not watching a Harry Potter movie.  Things unfold in rail operations slower than they do in cars, and  yet still, discovering the driving mistake happened too late to prevent it.
All this to say... events in an airplane typically happen a lot slower, giving pilots a lot more time to use CRM to work solutions.  Once the solution is agreed, the hard part - the use of judgment is done, and it's down to execution.

Although the young pilot in the OP's anecdote did fly with her instructor present, I don't see anywhere that she was required to do so. If she could legally have flown without her instructor, this argument doesn't really apply, although I'm not sure if that's the case or not.

"Things unfold in rail operations slower than they do in cars" - that is also true of braking, which means that human reaction time is not always the critical point of failure there.

^ What Piskvor said. Trains can take up to a mile to stop and do not have the luxury of turning like a car, let along maneuvering in 3 dimensions like an airplane. A train driver could be aware of an impending collision way before a car would even need to think about it and still not be able to stop it from happening.

@NuclearWang You can't solo an airplane (i.e. fly without your instructor) until you have a Student Pilot Certificate, which you can't get until you're 16.

@reirab: Indeed, in many situations it simply isn't possible for a train driver to become aware of an impending collision in time to prevent it (due to visibility-restricting things like tunnels and curves).

Regarding the comparison of the "set of principles that flying has as opposed to driving":
It's not necessarily the difference in the principles that matters;
both kinds of vehicles have ways to control how fast you go and the direction in which you go, and in both vehicles it is possible to lose control (and sometimes also to regain control).
But the principles of flight and the principles of driving are typically exercised under vastly different sets of conditions.
If pilots routinely flew along routes where there were solid obstacles just a few meters from the wingtips on either side (like the trees lining a country road) or if there were typically other aircraft flying in the same direction three seconds ahead of you and three seconds behind, and sometimes someone passing you in the same (or opposite) direction just a few meters away, I imagine the rules of flight would be somewhat different than they are now.
But those are not the usual conditions under which people fly.

A very large part of the population drives, which means that a large part of the population consider themselves authorities on driving, and qualified to tell other drivers what to do. Far fewer people are pilots, which means that the average person more or less trusts the professionals to know what they're doing when it comes to flying. This results in different regulatory environments.

Additionally, the same pressures mean that there is a much higher demand for driving instructors than flying instructors, which results in a necessity that becoming a driving instructor is easier than becoming a flying instructor.  In many jurisdictions, the only requirement for being a driving instructor is having held a valid driver's licence for some specific number of years along with a clean record, but flying instructors are generally required to hold actual specific qualifications for the purpose.

@Jules: Of course, given how much more dangerous driving is than flying, merely "having held a valid driver's licence for some specific number of years along with a clean record" is likely itself evidence that the person has the necessary skillset, eliminating the need for formal qualifications.

@Vikki that's incorrect, flying is massively more dangerous than driving.  It only seems safer because of the huge effort made to make it safe.  It's like saying "accounting for a large bank is easier than accounting for a child's game" simply because the children make errors more often than the bank.

@Harper-ReinstateUkraine: Tell that to everyone in the comments and other answers who make the opposite point.

@Vikki Regardless, the safety doesn't "just happen", it happens because of enormous work done by pilots and maintainers Level that playing field. Train 100 people to drive a car and train 100 people to fly an airplane.  All of them get exactly 8 hours of training that is comparable (not "classroom for cars, motion flight sim for planes").  Give them 100 each cars and airplanes maintained to an equal standard.  They must take a 500km journey.  Surely you must agree that if flying was safer than driving, that would mean the pilots would fare better than the drivers, yes?

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Center of Gravity, Aerodynamic Center and Center of Pressure, how do they connect?
I read an article that described static margin by taking the aerodynamic center and the center of gravity. It explained why the center of gravity has to be in front of the aerodynamic center for a stable aircraft. But how does center of pressure play into this? Couldn't the center of pressure be in front of the aerodynamic center and the center of gravity and still make the aircraft unstable? For example when the aircraft wants to gain altitude.
Then my next question arises, but I kind of have to understand the first problem... I'll just try to explain it the best I understand it right now.
Usually the stabilizers have a 'downwards' lift but say it doesn't. Say my aircraft just has two big wings.. where do I center the center of gravity around? How do I take the 'average' of both aerodynamic centers (or centers of pressure, depending on what's actually matters here) from both wings? I have a feeling that with two wings the center of gravity has to be somewhere between the two. And then say the aircraft has a proper stabilizer that has a downwards lift, how do I calculate where my center of gravity is? Or can I just take the main wings aerodynamic center?
If you explain it, feel free to use technical terms and forums. I want to understand this!
I guess my main question is the difference between the aerodynamic center and the center of pressure regarding stability and how it's related to the center of gravity.

This thread on a model airplane site may help -- https://www.rcgroups.com/forums/showthread.php?1870664-Static-margin-varies-with-trim-speed -- kind of messy, but worth digging through -- see also all the "related" ASE questions that are showing on the right-hand side of your screen.

Including this one -- https://aviation.stackexchange.com/a/39007/34686

This, this, this and this should answer your question.

Does this answer your question? What is the "Centre of Pressure"?

Center of pressure is to aerodynamic force what center of gravity is to gravity force.
Considering an airplane, gravity acts on everything that has a mass inside the airplane (each seat, windshield, landing gear, each blade of the turbofan and each rivet of the structure, payload, cables,... anything) but the whole effect can be ascribed to one single force acting in the centre of gravity of the airplane. The same happens with the aerodynamic force: it acts on every mm² of the surface of the wing but the whole effect can be ascribed to one single force acting on one particular point termed centre of pressure.
Changing the distribution of each mass inside the airplane changes the position of the centre of gravity: if the payload on a cargo aircraft is loaded toward the tail instead the nose, the center of gravity shifts backwards proportionally. The same happens with the centre of pressure: if the angle of attack of the wing or the pressure or speed changes, the aerodynamic force acting on each mm² changes proportionally as well as the location of the centre of pressure.
Having something that changes continuously makes things complicated. But luckily enough, both theory and practice show that, if the wing is thin, there exists a point in respect to which the aerodynamic force can be represented as the sum of a) one lift force linearly proportional to the AoA plus b) one constant moment. That point is called aerodynamic centre and is located at 25% of the chord at subsonic speed and 50% at supersonic speed. Being a well defined point, it is conveniently used as reference point to do calculations.
Regarding stability: this is a quite simple but lengthy concept and there are already many answers about it: I like this one the most.

The "Center of Pressure" is an older concept that imagines the lift from the wing, and any uplift or downlift from the tail, as combining to a create a single lifting force acting at a single point on the aircraft.
To a first approximation (ignoring thrust line effects, drag, etc) the airplane can only be trimmed for steady flight at a constant angle-of-attack, if the "Center of Pressure" is at, or directly above, or directly below, the CG.  (By "above" or "below", we really mean lying on a line drawn parallel to the direction of the lift vector.)
The Center of Pressure of the wing itself is not fixed-- it shifts forwards at high angles-of-attack and shifts backwards at low angles-of-attack.  This is destabilizing.
The Center of Pressure of the whole aircraft must do the opposite, if the aircraft is to be stable.  Note that we haven't yet said anything about what configurations or what CG locations make that possible.
The "Aerodynamic Center" is a newer concept that treats the wing's lift vector as acting at a given fixed point on the wing, usually the quarter-chord point, but also invokes an aerodynamic pitching moment.
That's just a start--

Good start! To continue: If the quarter point is chosen for the AC, the moment will be constant over AoA. Now your lift may vary but will still act at the same point. And the moment will not be affected by AoA changes. That makes calculations so much easier.

You have to separate two concepts; static stability and trim forces.
The weathervane analogy works well for this when conceptualizing static stability. A weathervane points into wind when its aerodynamic center, the point at which all forces induced by the wind is focused, is downwind of its pivot axis. Wind shifts, it points into the new wind direction.  It's statically stable; it wants to always point into the airflow.
If I move the pivot axis of the weathervane back to the same spot as the aerodynamic center, it won't point any longer and will just drift. Its static stability is neutral. If I move the pivot axis even farter back, it becomes statically unstable in the original direction, and will seek stability in the opposite direction. It'll switch ends.
Then there's trimming forces. If the weathervane is flat, it points into wind along its axis. But say I want it to be statically stable, but point at an angle off the wind, so that some side force is generated on the pole holding the vane up. I bend the trailing edge to one side. I'm trimming it. The local force created by the bent trailing edge will drive it out of alignment with the airflow until the opposing forces of the wind acting on the rest of the vane reaches equilibrium.
It will now be statically stable, and will point consistently at some angle off the wind depending on the amount of trimming force I applied.  I could call that Angle of Attack. So trimming forces modify the angle to the flow at which weathervaning forces (static stability forces) want it to point.
Turn the weathervane axis 90 degrees to horizontal. Same thing is happening. It wants to point into wind in the vertical plane, and trimming forces can influence the relative angle of the body to the wind at which it points, in the vertical plane.
Now take away the fixed pivot, so the weathervane is a free body. The pivot axis now becomes the weathervane's center of gravity. If the aerodynamic center is still behind the C of G, it will still want to point into wind. Absent any trimming forces, being free in space, if I throw the body, it will go in a very statically stable ballistic arc into the ground as it's drawn by gravity, maintaining alignment into the airflow the whole way. Like a lawn dart.
So to make it resist gravity and fly, I have to put lifting foils or wings on it, while keeping the aerodynamic focus point where I want it behind the C of G to keep it statically stable, and trim it to point into the air at an angle that makes the lifting foils operate at a positive angle. Now when I throw it, the body wants to align into the wind with the wings at a positive angle, and if the angle is right, enough lifting force is made to resist gravity and it flies straight instead of going into a ballistic arc.
On the wing, Center of Pressure becomes just one of the various influences that determine where the overall aerodynamic center's point of focus results. Because we need the wing to lift up, we need to apply trimming forces in the direction that forces the airplane to be statically stable - to vertically weathervane - at an angle to the flow that generates an up force. The trimming force therefore has to be opposite to the desired lift force, so it's down. But for stability purposes, the tail's force orientation is as part of the overall weathervaning effect, whatever it takes to maintain the trimmed angle of attack.
The tail is actually doing two separate jobs - contributing to static stability by adding surface area aft of the C of G, and generating trimming (and maneuvering) forces. Like a weathervane turned horizontal with the trailing edge bent up, it generates a down force to trim the aircraft to seek an angle to the flow that angles the wings into the flow to create lift. It also adds its area to the overall footprint of the whole aircraft that determines where the aerodynamic forces in the vertical plane will be focused, which must always be aft of the C of G (static margin). So that when the angle to the flow changes from an external source, being statically stable in its trimmed angle of attack, it will seek to maintain that angle.
Pitching moments, Centers of Lift, etc, are just sub-parts of the set of forces that result in the aerodynamic center, or Neutral Point, at any given time. If the aerodynamic center or NP, the sum of air forces acting on the fuselage, wings, nacelles, and tail is at x, while the C of P is at y, and the C of P of the wing moves aft, the overall aerodynamic center moves aft a little bit, increasing static margin, while also increasing the trimming force required to hold the same angle of attack. And vice versa when the CP moves forward.

Lots of great content in this answer-- but -- Re "The trimming force therefore has to be opposite to the desired lift force, so it's down." -- yet aircraft with lifting tails do exist, right?

If it's a conventional tail, to trim to a positive angle of attack, the tail has to provide a downward moment to force the mainplane into a positive AOA. If the trimming moment is up, the mainplane is being forced to stabilize into a negative angle of attack. If the tail is lifting to support the plane, the trimming force balance has to come from somewhere else, probably from the front wing, and you have a tandem wing airplane. Remember that it wants to weathervane into the flow, and you want it to weathervane at a specific angle to the flow by trimming it. Think it through what it takes.

The trimming force comes not only from the tail, but also from the weight. If weight acts behind the center of pressure of the wing, the tail needs to contribute a positive force. This does not mean that stability is lost: Stability does not depend on the forces themselves but their change with angle of attack. For static stability you need to think in their derivatives over AoA, not the forces themselves.

I like to use "weathervaning" to describe the change with angle of attack. But if the weight is acting behind the wing, you have a tandem wing design and to trim it to achieve a stability point at some angle to the flow, the trimming force balance is different, coming from vertical lifting force balance between the front wing and aft wing.

The aerodynamic center is a point on an airfoil where pitching moments do not change with Angle of Attack.  This holds true for symmetrical airfoil.  It moves forward a bit with cambered asymmetric airfoil (like most wings) when AoA increases.  This is where "tail feathers" like an arrow help.
A plane can be built with the weight right at the AC, but how do we control it?  2 ways:

Move the weight (hang glider)
Move the center of pressure (center of lift) with aerodynamic controls

for example when a plane wants to gain altitude

Gaining altitude is done by increasing thrust at a given trim speed
BUT, as you perceived, how do we rotate our aircraft to take off?  This is where you are rolling down the runway, reaching takeoff speed and you do what ... increase elevator back pressure to increase Angle of Attack.
Easiest to understand when you push the elevator down. More positive lift is created at the tail.  The center of pressure moves back.  The nose angle of attack reduces.  Pull the elevator up.  Less lift in the tail, center of pressure moves forward.  The nose angle of attack increases.
That brings us to "static stability" or speed control.  If you want a glider that is thrown from a hill top, (in free flight) to smoothly glide down for a few hundred feet, set the weight CG a bit forward of AC (usually) < 1/4 chord from the leading edge, and have your tail with less of an angle of attack than the wing.

Experiment with moving the weight around.

Once you have some idea of how the plane glides best (in a straight line all the way down with the greatest distance), you can move on to bringing the weight back and lessening the "downtrim" of the tail. This makes the plane better in gusts$^1$ as long as it is not so far back to make it directionally unstable!.
Now we can have a "lifting tail", which can even "morph" into a tiny canard and a giant tail as weight keeps moving further back.
But, walking before you run may be best.  Build a single wing classic glider.  Build many of them.  If you make it to flying full scale, the benefits of a glider foundation will be priceless.
$^1$ not as "pitchy"


text:
How to Calculate Required True Airspeed to maintain desired ground speed?
Working on programming my own E6B and am stuck trying to calculate the following problem from Sporty's E6B:
Given wind info and desired speed/course, what airspeed/heading should I have in order to maintain the desired speed/course mentioned?

Example:
Inputs:

Wind Direction = 60
Wind Speed = 14
Desired Course = 43
Desired Ground Speed = 100

Outputs:

True Airspeed required = 113.5
Heading required = 45

I have already solved the required Heading part by doing the below (this is JS code):
windAngleRad = toRadians(windDirection - course);

crosswind = windSpeed * Math.sin(windAngleRad);
headwind = windSpeed * Math.cos(windAngleRad);

tas = Math.sqrt(Math.pow(groundSpeed - headwind, 2) + Math.pow(crosswind, 2)); (THIS GIVES WRONG ANSWER)

driftAngleRad = Math.atan(crosswind / (groundSpeed - headwind));
heading = course + toDegrees(driftAngleRad);

toRadians/toDegrees do the obvious, Math.pow is exponent, Math.atan is
arctan

I have seen images like the one below, which make it seem like I have everything I need, but I am not sure how to solve the theoretical missing side of this triangle (TAS & HDG).

Trigonometry is not my area of expertise, so I believe that is what I am missing here. The only reason I have the code above done is that I saw a breakdown of solving it online. People ask how to calculate GS from TAS but not the other way around... seems like required True Airspeed is not something people seem to be calculating very often.

With that being said, if anyone could help me understand how to solve this, I would greatly appreciate it.

Your TAS formula is taking GS (green leg) and subtracting the wind) and then adding the crosswind^2.  It seems to me that it should be GS^2 + wind^2.   sqrt((green leg)^2 + (red leg)^2 )

@wbeard52 Pythagorean Theorem then?
That doesn't give me the expected results. Wouldnt the Direction have something to do with it as well? Because wind speed could be in any direction, with you or against you but the direction would give you that info of "Hey that 15kt wind is slowing you down, buddy."

The "brute force" approach would be to simply calculate (x,y) coordinates for the tip of the green arrow (ground speed) using sin and cos, go from there to the origin of the red arrow and then you found yourself at the tip of the blue arrow. Of course, you have to account for compass headings pointing up at 0° and increasing clockwise and mathematical angles pointing right at 0° and increasing counterclockwise.

I don't know if this will get you what you want. I programmed this a long time ago and don't remember why I did things the way I did and the code comments aren't very helpful now.
This image shows the inputs required to calculate various things involving wind triangles:

This image is the result I get using your parameters:

This code snippet is C++/CLI, but I think/ hope that it can be deciphered. I don't know why I used the law of cosines in this calculation. The angles have been converted to radians.
        double angle = 0;
        angle = windDir - trueCrs;
        if (angle < Math::PI)
        {
            angle = Math::PI - angle;
        }
        //Law of cosines
        tas = Math::Round(Math::Sqrt(Math::Pow(windSpd, 2) + Math::Pow(gs, 2)
            - 2 * windSpd*gs*Math::Cos(((angle)))), 0);

I know C++ so yeah this is 100% readable. Also tested with numerous random inputs and they all match. Thank you very much! Also, I would be very interested in other aviation programming you did, it sounds awesome and more in-depth than what I was doing.

I'm glad I could help! In the case of the wind triangles, the program also draws them. The way I made the form, the drawing is quite small and depending on the parameters, the components can be hard to see, e.g., those in your question. There are a north arrow, wind vector arrow and course and heading lines shown in different colors. If you aren't aware of it, there is a website with formulas for calculating many things: https://edwilliams.org/index.htm The aviation formulary link is in the first sentence on that page. You might find something useful there.


text:
Average salary and hours of a survey pilot?
I’m wondering what the average annual pay and hours flown are for a Survey Pilot? Namely in the UK.

So the next logical question is what does a survey pilot do in the UK?

@JuanJimenez Well, overflying pipelines for maintenance purposes, aerial photography, wildlife observation, and reconnaissance. I’m sure there are other roles I’m unaware of as it seems to be a very broad industry.

If this question is related to this question on aviation careers, then be advised that many survey missions will in the future be performed by unmanned aircraft. They may still use a pilot for a while, but the pilot will be firmly on the ground. I would not recommend this as a lifelong carreer.

Thanks @DeltaLima, will take this into account. It seems like a very fun job but I can imagine they will rather have drone operators flying than pilots relatively soon.

I agree with @DeltaLima, most of this work is already being done using drones, so if this is what you want to do you will have to charge what drones charge. Good luck.


text:
Radiotelephony Practices of American Pilots in Comparison to ICAO Standards
As a commercial pilot with experience in various airspaces, including frequent interactions with American pilots, I've noticed a distinct difference in their radiotelephony etiquette compared to the ICAO standard phraseology. The communication style often appears more relaxed, diverging from the standardised approach and including additional 'filler' phrases.
For example, here are a couple of phrases I've recently encountered in London airspace, which differ from the ICAO norms (airline name hidden for anonymity):

Observed Phrase: “London, this is Belta 3XR with you, cruising at level three five oh”

ICAO Standard: “London Control, Belta 3XR, Flight Level Three Five Zero”

Or the slightly more eyebrow raising:

Observed Phrase: “Hey London, Belta 324, ready to go down”

ICAO Standard: “† Belta 324, request descent”

(† addressing London Control probably not required as unlikely to be the first radio contact)

These instances highlight a casual approach that differs from the ICAO standards. My intention is not to criticise American pilots but to understand the broader context:

Regulatory Perspective: Are there any initiatives by the FAA and other aviation influencing authorities in the USA, to encourage American pilots to adhere more closely to ICAO standards in international airspaces?
Policy and Publications: Have there been FAA circulars or other publications addressing the radiotelephony practices of American pilots?
Safety Research: Are there independent studies suggesting that strict adherence to standard phraseology among pilots, including American pilots, enhances aviation safety? 1

I am keen to learn about any efforts towards standardisation and the potential impact on aviation safety, particularly regarding American pilots' practices in international contexts.

1 I find it interesting when reviewing the US Airways Flight 1549 Transcript that on a couple of occasions Sully replied quickly with standard phrasing such as “unable.”

Re "Observed Phrase:  "... ready to go down”"  -- had to laugh at this because me and my brother used to say this when we were tiny kids ready to be helped down from our hi-chairs at the table after finished eating-- who knew that we were practicing airline pilot lingo!

US is not so compliant with ICAO, for historical reasons (ICAO originated in Europe), many terms are not standard, starting with ATC unit names (e.g. TRACON/ARTCC instead of TC/ACC), AIP GEN 1.7 lists the differences, ordered by ICAO annex (section PANS ATM Doc 4444 for phraseology differences).

@mins thanks, this is what I am looking for - differences in the AIP. Though I am interested and inclined to disagree that “ICAO originated in Europe.” ICAO is a global effort led by various countries - the first convention of course being the Chicago Convention no less! The initial creation of ICAO was led by various countries,  the US having a predominant role in this.

Interesting. I didn’t realise that ICAO was seen as a European thing

Short answer
ICAO ATC phraseology is not mandatory, and is implemented by States members at different degrees, due to historical reasons:

ICAO ATC procedures, including phraseology, are not part of the standards and recommended practices (currently 12,000 SARP in 19 annexes), but of procedures for air navigation services (currently 6 PANS documents). PANS implementation is highly recommended, but is not mandatory.

Being not standards, ICAO State members may not list the local implementation differences in their aeronautical publications (AIP) at section GEN 1.7. However as PANS are important procedures, States usually give a summary of these differences in the subsection “PANS / Doc 4444”.

ICAO Convention is built on Paris Convention, managed between 1919 and 1944 by ICAN, the International Commission for Air Navigation. This convention was first intended to agree on sovereignty and security matters in European airspace, after the war. While ICAN was supported by the US, it was actively promoted by French Clemenceau and Albert Roper. It has been at the core of air navigation in Europe since then. When ICAO Convention was signed in 1944, Europe was already compliant, while other countries, including the US, had to manage important differences, and couldn't clear all of them easily.

Details follow.

ICAO standards
Collectively known as international SARP (standards and recommended practices), ICAO standards are adopted by ICAO Council and published as annexes to the ICAO Convention. They are intended to be included in each State member law. The Convention requires to enumerate which SARP have been adjusted or excluded locally (article 38), in the AIP of the State member, at section GEN 1.7.
ICAO Docs
ICAO Council also approves other practices, and recommend them. However because such practices are either not mature enough, contain too detailed elements subject to rapid change, or have a nature not compatible with the way the Council works, these practices are not given the status of standards. Instead of being published as annexes, there are published as “ICAO documents”.
State members have no legal obligation to use the procedures detailed in “Docs”, they only need to comply with the principles included in SARP. They have no obligation to explain in AIP GEN 1.7 how the local practices differ. However they are invited to do so.
ICAO PANS
In the area of ATC, the major documents are known as PANS (procedures for air navigation services), they include (links open directly pdf files):

Doc 4444, PANS-ATM (traffic management), merging previous PANS-ATC and PANS-RAC.

Doc 8168, PANS-OPS (aircraft operations) - Volumes I, II, III.

Doc 9868, PANS-TRG (training).

Doc 9981, PANS-ADR (aerodromes).

Doc 10066, PANS AIM (aeronautical information management).

Annex 10: SARP and PANS mixed
PANS-ATM are introduced by Annex 10, volume 2 (Communication Procedures including those with PANS status) which use is mandatory.
Annex 10, volume 2 provides both SARP and PANS for history reasons (PANS come from older Doc 7181, Radiotelephony Procedures, now superseded). SARP describe the principles to be used for communications and provide provide some phraseology details, which status is mandatory.
PANS are added to clarify details, but they are not mandatory. They are identified by the prefix PANS and written in italic. Examples:

5.2.1.5.8 The following words and phrases shall be used in radiotelephony [...]
CLEARED “Authorized to proceed under the conditions specified.”
UNABLE “I cannot comply with your request, instruction, or clearance.”

5.2.1.7.3.2.6.1 PANS.— As the aircraft may be guarding more than one frequency, the initial call should include the distinctive channel identification “INTERPILOT”.

Publication of differences with PANS
Explaining the differences with PANS-ATM is not mandatory. From Doc 4444:

5.1 The PANS do not carry the status afforded to Standards adopted by the Council as Annexes to the Convention and, therefore, do not come within the obligation imposed by Article 38 of the Convention to notify differences in the event of non-implementation.

However State must take it into consideration because:

5.2 However, attention of States is drawn to the provision of Annex 15 related to the publication in their Aeronautical Information Publications of lists of significant differences between their procedures and the related ICAO procedures.

FAA ATM procedures are described in JO 7110.65. As ATM procedures are critical, the major differences are actually included in GEN 1.7. Examples:
Doc 4444:

4.6.3.2 An arriving aircraft may be instructed to maintain its “maximum speed”, “minimum clean speed”, “minimum speed”, or a specified speed.

FAA:

The U.S. uses different speed control phraseologies. Specifically, Doc 4444 uses “Maximum Speed” whereas the US uses “Maximum Forward Speed”. Doc 4444 uses “Minimum Clean Speed” whereas the US uses “Slowest Practical Speed.”

Doc 4444:

12.4.2.4.2 a) COMMENCE DESCENT NOW [TO MAINTAIN A (number) DEGREE GLIDE PATH]

FAA:

The U.S uses only “begin descent” and does not speak to “Maintain a (number) Degree Glide Path.”

Other documents related to ATC phraseology

Doc 9432 (manual of radiotelephony) has the same status as PANS, it is not a standard, only recommendations.

European countries and US approaches
There are different approaches regarding the implementation of ICAO Docs. Certains States are more inclined to implement them than other, in particular European countries.
The Chicago Convention (1944) is directly based on Paris Convention (1919), a convention managed by the International Commission for Air Navigation (ICAN). ICAN was active between 1919 and 1944, it transitioned to a UN agency between 1944 and 1947 (OPACI), then became ICAO.
ICAN was impulsed in Paris at the end of WWI, with the support of the US, to deal with sovereignty of airspace.
Since 1919, ICAN/ICAO have been the core of the standardization process for international air navigation in most European countries. Remote from Europe sovereignty problems and less involved in ICAN, the US standardized their practices differently. Merging with ICAO recommendations is indeed more difficult, and done when it's worth the effort required from FAA, crews, ATCOs, etc.

In the US, there is no requirement for pilots to utilize standardized phraseology in ATC communications. I think most in the industry agree that the more standardized the communication, the level of safety increases due to reduced misunderstanding. In my experience (obviously with exceptions) the professional pilots adhere to standard phraseology. As a controller, you learn to listen to clearance read backs and pick out what you need to hear, or ask for clarification from the pilot. I believe that whatever a US pilot uses in US airspace will carryover when he/she flies internationally.

I’m surprised by the assertion that there is no requirement for pilots to utilize standardized phraseology in ATC communications in the US. Considering the USA’s status as an ICAO member state, I would expect the US AIP to align closely with ICAO standards, particularly those outlined in Annex 10 concerning aeronautical telecommunications. Could you clarify how this apparent discrepancy between US practices and ICAO Annex 10 is addressed within the US AIP? What differences from ICAO Annex 10 are given in the AIP?

Used to be a controller with Toronto Approach (a Nav Canada employee I presume) who would always acknowledge with "Rog".  It was a kind of a trademark. Guy was extra friendly. I think, to a certain degree, the informality brightens the mood you might say. I was always careful to be really cheerful and polite with ATC ("good morning" "see ya", "have a great one" where air time permitted). I thought it made everybody's day better and fostered goodwill. I think a stricter environment isn't much safer and is just less pleasant. Granted, oddball wording is a bigger issue b/c of the confusion risk.

@tedioustortoise, what Annex 10 standard is not being followed? The list of differences with ICAO standards is common for every country and is found in the GEN 1.7. https://www.faa.gov/air_traffic/publications/atpubs/aip_html/part1_gen_section_1.7.html

@Timbo my overall point is a distinct difference in radio etiquette compared to that described in: ICAO Annex 10 Volume II Chapter 5, ICAO Doc 4444 Chapter 12 and in ICAO Doc 9432


text:
When not cleared straight in for a VOR approach, how is this type of procedure executed?
You are flying to the GDM VOR on a 097 heading. The ATC clears you for the approach, but does not specify straight in. The procedure turn is marked by the barb and specifies remaining within 10nm. My assumption is that you would fly a procedure turn style course reversal, using the altitude of 3000 within 10nm, fly the 277 back course, then fly the procedure turn inbound. I would assume most times ATC would just clear you straight in however is there any documentation of this style of double PT/unpublished course reversal procedure?

If in doubt about what ATC wants you to do, ask!

@aeroengie, What do you mean by “this style of double PT/unpublished course reversal procedure“? I just see a single PT, and it is obviously published...

ATC will not clear you "straight in" for this approach because there is no IAF or IF which exists along the final approach course. There is only a procedure turn, which you must execute unless ATC issues you an approach clearance based on vectors to intercept final approach course. There being no FAF, the "approach gate" outside of which they would vector you will be on the GDM277 radial, 3.1DME fix. (Although center controllers are famously reluctant to issue vectors-to-final.)

When talking about approaches, you should limit your terminology to mean the same thing for you as it does for ATC. In other words, for a Category A aircraft:

ATC would not clear you for a Straight-in Approach unless you were inbound from the South for Runway 36 or inbound from the North for Runway 18. There are no Straight-in minimums for this approach, only circling minimums. To use this approach, you are required to fly a modified Traffic Pattern no lower than 1760 feet MSL until you reach a point where you can descend safely to the runway while maintaining cloud clearance. ATC will give you instructions on which direction to circle. In the absence of instructions, circle in the direction prescribed for Traffic Patterns in the US Chart Supplement and Sectional.
There is no Back-Course for a VOR. A Back-Course implies an ILS or Localizer transmitter. VORs transmit their navigation signals differently than ILSs and Localizers. There are Radials for each VOR dependent on your bearing from it. There are To-indications and From-indications for each Radial depending on your location on the extended Radial relative to the VOR. There is normal/direct-sensing and reverse-sensing for each Indication dependent on your Heading.
If you were flying inbound direct to the GDM VOR on the 097° Radial, you are East of the VOR flying Westbound on a heading of 277° Magnetic. The safe altitude at which to remain above is the Minimum Sector Altitude of 3300 feet MSL unless assigned otherwise.
You may request from ATC a Hold at the VOR to buy time to prepare for the approach or to lose altitude. Although, it is not part of the official Instrument Approach Procedure until the Missed Approach Procedure, you may use it to get established inbound to the airport or VOR on the 277° Radial instead with ATC clearance.
If you are not cleared for the hold, or accept clearance for the full procedure, once you pass the VOR, you may descend down to an altitude at or above 3000 feet MSL as long as you remain on the 277° Radial.
You may perform a Procedure Turn (starting with a left turn to a Heading of 232° Magnetic for 1 minute, then a right turn to 052° until reestablished back on the original Radial) anywhere along the 277° Radial as long as your aircraft remains within a 10 Nautical Mile distance from the VOR during the entire procedure. The general convention is to travel at least 2 miles or 2 minutes before starting the Procedure Turn.
Once you are established inbound on the 277° Radial with a Course and Ground Track of 097°, you may descend down to, but no lower than, 2400 feet MSL until you reach the Final Approach Fix which is the GDM VOR. Please be cognizant of the fact that when ATC Radar services are unavailable, other aircraft may be holding at the GDM VOR at or above 3000 feet MSL. It would behoove you to cross GDM inbound below 3000 feet MSL.
Once you have passed the Final Approach Fix, you may descend down to, but no lower than, 1760 feet MSL to start your Circling Approach. The Circling Approach May only be started if you have established visual contact with the runway.
If you never establish or are unable to maintain visual contact with the runway environment during the entire Circling Approach, remain on or return to the 097-From/277-To Radial until you reach the Missed Approach Point of 1.9 miles DME from the VOR (1 minute, 54 seconds at 60 knots ground speed). If you still have not established visual contact, perform the Missed Approach Procedure (a climbing left turn to circle back to the GDM VOR, climbing to hold at GDM at an altitude of 3000 feet MSL).
If, at any time during your descent past the Missed Approach Point, you can not maintain cloud clearance, circle back over the runway to join the Missed Approach Procedure.

—————————————————————————————————
Per the OP’s edit:

Remain at or above the MSA for the inbound heading from which you are coming or your assigned altitude.
Do not descend until you have crossed GDM on an outbound leg.
Once you have crossed GDM, utilize the hold to descend down to but not below 3000 feet MSL.
Notify ATC on whether you will proceed in on the inbound leg directly from the hold, or do the full procedure outbound to the Procedure Turn.
If no altitude loss is necessary, notify ATC of your request to proceed inbound on the procedure. You will have more than 1.9 miles to descend down to 1760 feet MSL (depending on where you get established on the Initial Approach course/leg).
Alternatively, you can intercept the procedure anywhere on the Initial Approach course/leg if cleared by ATC. Provided you do not start your descent to 3000 feet MSL until you are established on the procedure outbound or to 2400 feet MSL until you are established on the procedure inbound. Either inbound or outbound legs must be within 10 NM of GDM.

"other aircraft may be holding" — not any IFR aircraft, certainly. ATC can provide non-radar separation via altitude, and would, if necessary.

Also in your very first bullet point, you are referring to a straight-in landing, which is not what OP was talking about and (as you point out) not possible because this is a circling approach. Completely separately, and more to the point, ATC will never issue "Cleared straight-in VOR-A approach" because the 7110.65 4–8–1c prohibits it: "Except for visual approaches, do not clear an aircraft direct to the FAF unless it is also an IAF, wherein the aircraft is expected to execute the depicted procedure turn or hold-in-lieu of procedure turn." See also 4–8–1d and e.

When ATC clears you for an approach in a Non-Radar environemnt, the airspace around the airport is your protected airspace. As long as you stay within the confines of the published instrument approach, you may execute all, or any part of, the published procedure in order to reach the runway.
This is a rather unique situation because you just happen to be flying towards the airport on the inbound track of the approach. In this case a procedure turn is not needed and you don't need an ATC clearance to skip the procedure turn. This of course assumes you are low enough and can establish your location with DME or GPS.
Skipping the procedure turn will save you lots of time and the controller and/or other waiting aircraft will be happy you did. This is a Non-Radar environment and it is important that you communicate to ATC and other aircraft exactly what you are doing.
When you are within 25nm you can descend to the Minimum Sector Altitude of 3300'. Since you are already on the 097 Approach Course, at 10nm you can continue descending to 2400' to cross overhead the VOR.
Once past the VOR you may descend to 1760' and complete your circling approach to which ever runway you prefer.
If you do not have DME or GPS to accurately establish your position, or if you find yourself too high(poor planning?), you would need to overfly the VOR and then do some kind of course reversal.  The easiest way would be to hit the VOR and then do a righthand racetrack pattern while descending to 3000' to establish yourself on the 097 Approach Course.

Very good answer but I think OP is specifically asking hypothetically what if you're NOT cleared for straight in.

I edited my answer to provide more information.

Your answer might be correct in other countries, but NOT in the USA where this approach is located.

As long as you stay within the confines of the published instrument approach, you may execute all, or any part of, the published procedure in order to reach the runway.

No, AIM 5-4-7(d) says, "Except when being radar vectored to the final approach course... pilots must execute the entire procedure commencing at an IAF...."

When you are within 25nm you can descend to the Minimum Sector Altitude of 3300'.

NO! The MSA is for emergency reference only.

Why are you assuming this is a non-radar environment? What justification can you provide for your assertion that a PT is not required?

Dave-CFII is correct; you have to do the entire procedure starting at an IAF (or IF if ATC allows for a straight-in), or if being radar vectored to FINAL.  ATC will not vector to final unless the final course is depicted on thier scopes (and the pilot has to ask, or ATC will initiate it, if it is).  Otherwise, a "double course reversal" is always required.  ATC cannot, and will not, vector to intercept the R-277 outbound in order to skip the IAF.  AIM 5-4-7 paragraph (f) and (i)


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Can wing sweep decrease total drag force at low-subsonic speeds?
From  experience everybody knows if you put your arm out of car window at high speed(150km/h), it's a lot easier to hold arm angled backward then hold arm straight out(prependicular to airlfow).So conclusion will be that drag force is reduced..
Can wing sweep in same manner reduce total drag force at speeds up to 250km/h?

Pulling angled "beam" with rope in water will be easier than if "beam" is prependicular to flow.Right beam has smaller lift force but also less total drag force.Is this correct?

While the question is valid, the experiment you describe is flawed. You reduce the effective "wingspan" by the cosine of your arm angle, and thus the moment felt at the shoulder joint by the cosine squared. At 45° this cuts the moment in half even if the drag per unit of of wingspan is the same.

@Sanchises Shoulder will feel lower  moment by 1,4times with angled arm at 45degrees,cosine 45=0.707 (1:0.707=1.4) if drag force remain the same.But I think drag force will also reduced.

related: Is there any benefit of using a swept wings at low-subsonic speeds?

@ManuH This topic was  about swept wing in general,here hope for detail explanation about how sweep affect on drag in low-subsonic..

@member Yes, total drag will also be reduced (the frontal area is reduced because your arm doesn't "stick out" as far), hence the cosine squared so half the drag not 0.707. Also in your second image, is it on purpose that the wing span is smaller on the right-hand side? For a more fair comparison you should make the beam longer on the right side so that the width projected onto the flow direction is the same.

@Sanchises Beams  must be the same length,that represent same spar length and area.

Sweeping back a wing of fixed spar length and area does decrease form drag. However due to both its lower aspect ratio (span/chord) and sideways flow effects, it increases induced drag and decreases lift, so that the net L/D ratio or efficiency of the wing falls.
Whether the absolute amount of drag goes up or down depends on other factors, such as wing loading and angle of incidence. In most situations drag would be higher. Where it is less, other design optimisations such as reduced spar length would offer greater improvement.

Just keep in mind that in my case,wings are not produce same lift force.Sweep back wing produce smaller lift,because area and spar length are same in both case.

@member2017 There are a lot of parameters you need to clarify before exact comparisons can be made, wing loading, spar length, chord, angle of incidence, airfoil profile and aircraft weight being just a few that spring to mind.

@member2017, comparing wings producing different lift is mostly meaningless. The wing needs to produce lift to balance the weight of the aircraft, so for a meaningful comparison the wing should be producing the same lift. It may do so at different lift coefficient and/or different angle of attack, and may be able to produce different lift at its critical angle of attack, but the points you compare should generally be for the same lift. The bird does not become lighter when it sweeps its wings for faster flight or heavier when it stretches them out for soaring.

@JanHudec I agree with you,but I need this comparation for some other purpose.I just want to know if swept wing will has less lift and less total drag compare to straight wing?

@member2017 then you have to specify how you match the flow conditions.

@JanHudec How do you mean?

@member2017, well, if you are not comparing same lift, you can be comparing same angle of attack, same wing loading, same coefficient of lift…

@JanHudec I just have one wing and two posible positions, straight and swept ,both at same AoA,airspeed 50kts..that is all I know,everything else is unknown

The main issue is that sweep does not benefit low speed and sweep adds dangerous behaviors. Wing sweep is needed only for the trans-sonic speed range, slower than mach .65 or faster than mach 1.5 and they do not add benefit.

If sweep is sufficient, it reduces drag even upwards of Mach 1.5. As long as the leading edge is subsonic, drag is substantially lower.


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Can you verify that this aircraft is not a variant of the T-34 Mentor?
On this page, near the bottom, the aircraft below is identified as a T-34. I'm wondering if that's correct, but before I contact them to point out a possible mislabeling, I'd like to find out what it is or is not.

UPDATE -- I sent en email to The Catalina Island Conservancy, and they have changed the image to correctly show it as a Nanchang CJ-6.

Looks like a CJ-6. Popular as an affordable "warbird" type of aircraft, without the rarity.
Various other images of the CJ-6 that seem to match up to what you posted.

I would go with this answer; that’s no T-34

agree. The T-34 doesn't have a cranked wing or knee-type main gear, nor the radial engine or the very long canopy. but the rudder shape is similar...

Which itself is a Chinese copy of the Soviet Yak-52

@CarloFelicione "This is not the T-34 you are looking for."

It is in fact a Yak-52, Soviet era trainer aircraft.
It indeed looks nothing like the T-34.
See Wikipedia for more information

I thought it was a Yakovlev of some sort at first glance, too. But it's certainly not a Yak-52: they have straight wings but this plane has gull wings.


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What planes are good for both Aerobatics and XC?
Aside from Van’s planes, are there any planes capable of both XC and Aerobatics?

What are you criteria for "capable"? I'd say pretty much every airplane has some capability of both.

@FredLarson this is true… I’m referring to planes that are “known” to be good for both… e.g. a Van’s RV7/14.

“Capable” and “good” are both very subjective.  Got any specific criteria you are looking for?  (Max Gs, max range…). Number of seats?  Cost?!

@MichaelHall I realise this is a very vague question — i suppose if I had to give you numbers, a touring plane capable of pulling +6gs? or vice versa, a plane you can use in competitions but also can be used to fly comfortably for long distance (say 5h endurance at 75% power)

Aerobatic aircraft (particularly high performance competition aircraft) are typically less stable than other GA aircraft.  Consequently, they take a higher degree of attention for cross country flights.  You could perhaps install an autopilot and servos, but all that weight takes away from aerobatic performance.  In a similar vein, a strict competition aircraft is going to be barebones in terms of avionics -- day VFR only, and nothing that adds extra weight.  In a cross country aircraft, I'm looking for dual controls, all the fancy nav, wx, traffic gizmos, seats in the back for family, etc.

@RobMcDonald You make a fair point on the weight and avionics. Dave answered about an aerobatic Bonanza which bridges the gap between the two… how i do not know

Long EZs & Berkuts fit the bill. (Not much space for baggage though)

Back in the early 2000's I remember seeing an airplane parked at Sun-N-Fun that fits your bill.  It was a bubble-canopy Skyraider -- with room in the back for plenty of camping gear & as well as the wife and kid.

The Cessna 152 Aerobat is certified for aerobatics and also has passible XC performance (depending on what you want to optimize). You can fit two statistically small people and a bag with 100Kts cruise which gets you around a bit faster than a car depending on headwinds. Its also a widely produced airframe, easy to get parts and A&P's for.
There is apparently an aerobatic Bonanza out there which could be a decent candidate but you would need to actually find one.
Bob Hoover made it clear you can fly some aerobatic maneuvers in a Shrike Commander which is a decent sized twin for getting places.

Not so sure I'd want to be doing aerobatics in a beat up 50 year old Aerobat lol.


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GNSS approaches: Why does LNAV minima even exist? Wouldn't all aircraft fly to LNAV/VNAV or LPV minimums?
I am new to instrument flying and am trying to wrap my head around the different types of GNSS approach minimums. I am having an issue understanding why LNAV minimums exist. My understanding is, if you're GPS is not WAAS-certified, then you are flying your approach down to LNAV/VNAV minimums. In this case, the lateral guidance is provided by SBAS (your GPS), and the vertical guidance is provided by your barometric altimeter. So...my confusion here is...since most aircraft have barometric altimeters, when would you ever use the LNAV minimums? Since every aircraft contains some sort of altimeter (your vertical guidance), then why does an LNAV approach even exist? Is it only for the case of an aircraft having a GPS and a non-barometric altimeter (i.e. a radio altimeter)?

Welcome to Av.SE!  A small point, a baro altimeter is required for lots of things beyond approach minimums, and a radio altimeter is expensive & only required for some fairly specific things like Cat II / Cat III minima, plus some more advanced GPWS systems (more advanced than terrain warning that you can get with GPS + an iPad, at least).  So anybody that has a radio altimeter will certainly have a baro altimeter (or two) as well.

Adding to this… The misunderstanding in the question is due to thinking that LNAV/VNAV requires only a barometric altimeter and not a Baro-VNAV system.

Exactly what Timbo said.  I am often told by people that they can fly to the Baro-VNAV minimums because their autopilot “obviously” understands barometric altimetry because it has altitude hold, vertical speed modes, and altitude preselect.  This is not correct.  The slope precision required for a glidepath can only be met by a navigator that has a baro-VNAV approved Air Data Computer.  Common in transport aircraft, but not common in GA aircraft.  The ubiquity of WAAS GNSS approaches has greatly diminished the justification for the cost of certifying an aircraft for baro-VNAV.

In LNAV/VNAV approaches, the vertical guidance can be provided by WAAS, or it can be provided by a baro-VNAV system.
On an LNAV approach, there are step-down waypoints just like on any other non-precision approach. The pilot uses the altimeter to manually adhere to minimum altitudes.
On an LNAV/VNAV approach, the avionics compute a glideslope and provide vertical guidance all the way to the decision altitude, so the pilot can "chase the needle," just like a precision approach. The vertical guidance can be provided either by WAAS or by the barometric altimeter ("baro-VNAV"). Not every airplane with a barometric altimeter is capable of using it in this way.
So LNAV approaches are the only ones that can be done by aircraft without baro-VNAV or WAAS available. There also can be restrictions on the other approaches- for example, baro-VNAV approaches are often not allowed if it is too cold, due to the altimeter errors caused by low temperatures.

One reason Baro-VNAV might be unavailable: "Baro-VNAV and VDP not authorized with _______ altimeter setting" - note on an approach chart for an airport with a part-time tower.. Going from local altimeter setting + LNAV/VNAV mins to remote altimeter + LNAV mins changes the mins from a DH that's 282' above the runway to an MDA that's 458' above (if baro VNAV is your only option), so that's a significant difference.


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Why arrow wings are more efficient than delta wings?
From page 29 of this slide (https://archive.aoe.vt.edu/mason/Mason_f/SupersonicPres.pdf), an arrow wing has higher lift slope and lower induced drag slope than a delta wing with a straight trailing edge, all else being equal. Could anyone explain the mechanism of trailing edge sweep angle vs. lift and drag?

A short clarification while waiting for an answer: what you see in that plot is the slope of the lift coefficient. Higher slope means that the aircraft is more sensitive to changes of angle of attack but does not imply that the maximum lift coefficient is higher.

Arrow wing??? That looks like a swept delta to me.

Sophit: I was asssuming these two wings don’t generate much lift around 0 degree AOA. Then if we integrate Cla from 0 degree AOA, a higher slope everywhere results in a higher lift. But you are right, I shouldn’t make that assumption in the first place.

@SOAR1123: I was thinking if the fact that the coefficients look better on the arrow wing isn't just a side effect of the nondimensionalisation with the smaller wing surface of the arrow wing in respect to the delta wing

@sophit: On previous page it stated “pressure at TE don’t have to come together in supersonic like in subsonic”, leading me to believe it might has something to do with some shockwave / TE interactions. Besides, if two wings (with presumably same airfoils) have different Cl (or Cla), there must be some 3D effect causing different pressure distribution. So I personally feel its not a problem with wing area.

“Previous page” refers to slide 28 of the document, that is.


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MOC for CAT III missed approach segment
Hello what is the MOC (minimum obstacle clearance) for missed approach segment for CAT III ILS minimum ?


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Using an experimental aircraft to carry patients for medical treatment?
I am interested in doing flights for organizations that connect pilots with patients. I am also interested in purchasing a Sling Tsi and I am wondering if those two things can be combined since it is an experimental. I don't see anything in the reg that would prevent that.
Thanks

This is what Angel Flight West says about it, "At this time, it is not permissible to use experimental or non-certified aircraft for passenger missions. Experimental aircraft may, however, be used for missions transporting blood or for any non-passenger missions."
https://angelflightwest.org/pilot-page/

The easy question first: receiving any money for doing so is illegal compensation. Sharing expenses doesn't apply because you don't have a common purpose with the patient.
It is likely that such an operation would require a part 135 certificate, since the business you are describing could be considered to be holding out a willingness to transport people for compensation. But even if you have a commercial certificate and think that it should be legal under part 91, 14 CFR § 91.319(a)(2) forbids it in an experimental aircraft:

No person may operate an aircraft that has an experimental certificate [...] Carrying persons or property for compensation or hire.

The FAA interprets "compensation" very broadly. If you receive anything of value, even if it's abstract or less than your expenses, you must fall into a specific exception that allows it or you are receiving illegal compensation. There are many exceptions for certificated aircraft, but for experimental aircraft there is only glider towing and flight training.
Otherwise, I think it should be legal as long as you follow all the other restrictions of 14 CFR § 91.319 and of your airworthiness certificate. Some of these might be a problem:

Unless otherwise authorized by the Administrator... no person may operate an aircraft that has an experimental certificate over a densely populated area or in a congested airway

Each person operating an aircraft that has an experimental certificate shall [...] Advise each person carried of the experimental nature of the aircraft [and] Operate under VFR, day only, unless otherwise specifically authorized by the Administrator

The day VFR and densely populated area restrictions are theoretically problematic but can be waived on your operating limitations. So in practice this doesn't really matter.
Needing to inform the patients that you are flying an experimental aircraft is probably more problematic. I expect the reaction of most people to being told that they are being flown in an "experimental airplane" is "hell no I'm not."

Hi Chris, Thanks for the response. Sounds like experimental is definitely out for this plan. So for standard category it sounds like you think it would may need to be part 135. The push back on that I would say is that this wouldn't be a willingness to transport for compensation if I was only compensated for the expenses of the flights and not a salary or hourly fee for my own time. Thoughts on that?

The FAA definitely considers being compensated for the expenses of a flight "compensation," so that argument is a non-starter. There may be an argument somewhere that you aren't being paid by the people you are flying, so it isn't really common carriage (though it is still compensation). I would 1000% talk to a lawyer with experience in aviation before I'd think about starting an operation like this though.

@Tricio I suspect you might also have tax issues if you create a "non-profit" whose sole existence is to pay you to fly an airplane. But I'm not an expert on that topic. ;)

I agree that anything "for hire" and experimental do not mix, but the statement about day vfr and densely populated areas is way overblown. It is easy to get this allowed in operating limitations as long as the aircraft and equipment support it, but that is true for production certificated aircraft as well. Also, I fly experimental and few people refuse. Never has anyone said anything like "hell no" as you speculate.

@Pilothead Friends and fellow aviation enthusiasts, or strangers who know nothing about general aviation? I have family members who have told me in no uncertain terms that they would never go up in something I built in my garage. ;)

Regarding the day VFR and populated area thing, I agree. I didn't intend to make it sound like a large problem. But it's something to think about if you're buying an experimental aircraft to make sure it doesn't have operating limitations that will be a problem. I've recorded the relevant phrases to make this clearer.

@Chris, I made a few edits, including the broader scope of the CFR which makes it clear that experimentals are permitted to fly nighttime/IFR and over densely populated areas. Which is a good thing, because 99% of them probably do! Revert them if you feel they diminish your answer.


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What is this 3-engine beast?
What is this 3-engine beast? It has an unusual 6-bladed propeller as well.

Hello Tiger, welcome to aviaiton.stackexchange.com. Can you credit the photographer and the source of the photograph and put in a link to the website where you found it? We appreciate it if people are credited for their work.

Vickers Viscount C-FTID-X
Pratt & Whitney Canada's PT6 test bed with a PW100 mounted on the nose.
01/22/2007. Remarks by Jack McKillop:

"This aircraft made its first flight on February 25, 1959 and was delivered to Trans Canada Air Lines (TCA) on March 8, 1959 registered CF-TID with fleet number '648'. TCA was renamed Air Canada on June 1, 1964. It was leased to The Sarcee Club between October 1971 and June 1972
It was sold to United Aircraft of Canada on November 27, 1972, and reregistered C-FTID-X, it was used by Pratt & Whitney of Canada for flight-testing the PW124 turbo engine with six-bladed Hamilton Standard advanced propeller to power the British Aerospace ATP. In October 1989 it was withdrawn from service and stored at St. Hubert, Quebec. As of this date, the aircraft is no longer registered in Canada."

Wow, that looks hideous!

It's obviously been lying to someone.

Well, that configuration does put the test engine and prop out in clean clear airflow, and.....and... erm...  Ok that's it, that's the only redeeming feature I can think of. That thing must be a total pain on takeoff and landing, it would induce the most interesting vibration modes in the airframe, and limits pilots to people with strong stomachs, prone to neither vomiting in disgust not falling down laughing at the sight of their vehicle. Deaf would help too, with a rather strong engine mounted directly in front of their cockpit and very little to dampen the noise.

Not the prettiest bird ever. And 5 engine (not 3 as supposed by the OP) to boot! It's a test bed, though, and isn't designed to win beauty contests. Poor thing... I'll bet she's got a great personality!

@PcMan I can't imagine that being deaf would help much considering the vibration...

I bet she's got the visibility of a Concode on landing.

@FreeMan "A plane called Sue"...

Wait... You're telling me that's not a plane that had a cargo container dropped on its nose?

I like the fact that someone's gone to the trouble to extend the paint job over the nose, including the racing stripe.  I suppose it was worth a try, but I don't think anything would help that.

Awesomely ugly. Might win "ugliest aircraft ever made", if it didn't get  too many people thinking it had  left ugly behind and progressed to surreal.

I wonder where that ugly dog rests now.


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ID this plane with a white body and a blue stripe
Going through my Dad's things I found this plane and would love to know what it is.

I hope your father wasn't on board for that particular landing - it looks like that one may have been a bit rough!

Any idea where the picture was taken?

I think it was around Terrace, BC

To add to Tevildo's answer, the livery for the Scottish Aviation Twin Pioneer appears to be this one

from here which per this seems to have been leased to Dampier Mining Company; that picture was taken somewhere near Sydney Australia. I suspect there aren't many of these planes so it might be possible to get to an actual airframe.
Following up on harshbutfair's detective skills in their answer, it looks like it might be C-GNIS. Here's a picture of C-GNIS. This page (search for C-GNIS) details its history. At some stage it was indeed parked and vandalized.

Apparently it was then restored (perhaps by the OP's father?) and at least recently was at the Quesnel Heritage Aircraft Museum in BC Canada.
Quesnel Heritage Aircraft Museum, Quesnel Airport, PO Box 52, Richard Store, Quesnel, British Columbia, V2] 5E5. Tel: 250-747-2542 - if you want to visit it!

The paint sure looks the same, just the name scratched off maybe.

@Sunny I think harshbutfair found the registration and I found a picture and a history of it :-)

Yes, that is the very plane.  My Dad was part of the group that pulled it out of the bush and brought it to Quesnel.  My thanks to all of you!

@Sunny If you're happy with one of the answers you've received, you can accept it by clicking on the "tick" icon.

I have not used this type of forum before. What is a tick icon?  The triangle?  thank you, :)

It looks very much like a Scottish Aviation Twin Pioneer.  The stub "wings" from the lower fuselage to the undercarriage are quite distinctive.

Image from RuthAS, via Wikipedia.

Thank you very much!  My Dad was part of the recovery team that salvaged the aircraft.  Sadly I don't know what became of it.

You can almost make out the registration on the left side of the image. It looks like it starts with C- followed by a G, and then ending in an S. From searching for Scottish Aviation on Aviation History Canada I believe it could be C-GNIS.

I think we have a winner. Also see https://www.goodall.com.au/australian-aviation/twin-pioneer/twinpioneer.html which lists the history of C-GNIS (search for it). Upvoted. I might stick the pictures in my answer!


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Why do high altitude sky-divers say 'Exit' multiple times?
This is something that has always puzzled me.
https://sndup.net/6vn8/a
Unfortunately, I can't find a video in which I heard them say it, but right before they left the plane, I heard

Exit exit exit exit exit exit

through a radio or megaphone.
I found audio of this, but maybe you might not be able to benefit from it because there are no visual cues.

I can't find the video I saw three years ago, but I did get an audio version.

Just a guess, but exiting an aircraft in flight, being a terrifying (and thrilling) experience, might require some extra encouragement. As well as assurance that your weren't just saying "exit" casually in a sentence, but over the sound of rushing air and anticipation, you mistake it for an instruction.

I thought the proper term is Geronimo


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Are agricultural pilots allowed to use a highway as a runway?
I lived not far from a spray pilot who had had a hangar in his yard in the country but right off the highway. Would he need some special endorsement to use the highway as a runway?

While not strictly against FAA regulations, local ordinances would probably be the controlling factor here. The other problem is making sure that it is safe to use (people, cars, power lines, power poles, mailboxes, etc). There is no special endorsement for using the highway as far as the FAA is concerned.

Perhaps doesn't apply now, but back in the 1950s my father was an agricultural pilot, and I remember him using country gravel roads on occasion. I don't recall him ever using a paved road,

This question is very closely related, perhaps even a dupe. Essentially, the FAA doesn't care very much about where you take off and land - as long as you do it safely! - but the landowner/county/state often does. So the limiting factor is local land zoning and other laws, not FAA regulations.

ok thank you for the answers

There are many highway segments that are on purpose designed to be usable as runways list here. But this is more for the military.

My answer is colored by having spent a couple of years as an ag applicator.
There is no endorsement needed to use the highway as a runway.
Practically, it is done less now than 30 years ago.  Also more states have codes now which prohibit operating aircraft off public highways.
Locally an operator used a paved road which terminated at an interstate, where all the houses on that road were owned by the same family. In 1978 that operator had to scramble, because the town decided to enforce a code prohibiting aircraft from using town roads for landing and takeoff.  The only other place I have seen it today is in parts of the northern mid-West. I am not familiar with their local codes or state codes.